Electric railway-signal apparatus



4 Sheets-Sheet 0. GASS-ETT.

Electric Railway-Signal Apparatus. No. 228,187.

PatentedvJune I, 1880. XA Q7/L31 illu . u Ju.,

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4 Sheets-Sheet 3. 0. GASS'ETT.

4Electric Railway-Signal Apparatus. No. 228,187. n

Patented Jurne 1, 1880.- V V 4Sheet's-Sheet 4. 0. GASSE-TT. ElectricRailway-Signal Apparat-us.

, PatenifedJune maso.

Na. 228,181.I

"UNITED- STATES PATENT Ottica@ OSCAR GASS-ETT, OF BOSTON, MASSACHUSETTS.

ELECTRIC RAILWAY- SlGNAL APPARATUS.

SPECIFICATION fori-ning part of Letters Patent No. 228,187, dated June 1, 1880.

Application liled December 22, 1879.

To all whom it may concern:

Be it known that I, OSCAR GASSETT, of Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in Electric Railway-Signal Apparatus, of which the fol`- lowing description, in connection with the accompanying drawings, is a specification.

This invention relates to electric=signal apparatus for railroads, and is herein shown as used in connection with that class of apparatus operating; with a closed circuit, as described in reissued United States Patent No. 5,958, to which reference may be had.

g In some of the systems of electric railroadsignals now in use, when a train enters upon a section of the track it operates a so-called block-signal, which remains in a certain position as long as the train is on that section, thereby giving warning to succeeding trains that the said section is occupied. Devices have also been employed whereby the opening of a switch in the section operates a signal at the end of said section, thereby announcing to approaching trains the fact that the section is unsafe.

It is obvious that a signal so controlled by the switch affords no protection if the switch be operated or opened after the train has already passed the signal, but before it reaches the switch.

My present invention consists in the employment, with such a signal operated by the opening of the switch or by the presence of a train on the said signal-section, of a locking device for said switch to automatically lock the switch arm or lever while the switch is closed and the signal at d aDger, the said locking device being controlled by the signal at the end of the section in such lnanner that while said signal indicates danger;7 as after a train has entered the section, the switch is locked and cannot be unlocked to be moved by the operator at the switch alone.

The locking device is operated to unlock the switch by an electro-magnet and battery in a local circuit between the switch and signal,

and, as herein shown, the switch is unlocked whenthe local circuit is closed; but the said local circuit passes through certain points in the signal mechanism in such manner that said circuit is open while the signal indicates danger, and consequently the switch cannot be moved until the circuit is closed, and in practice the circuit-closer for doing` this is placed at a distance from the switch, herein shown as at the signal; but it maybe any where so that the switch cannot be moved by the man at the switch alone.

As herein shown, the local circuit is also open at points in the switch-moving mechanism, the said points heilig closed by releasing the usual hand-operated switch-holding mechanism.

It will thus be seen that the block-signal is so connected in a circuit controlled by the train and the switch mechanism so connected in a circuit with the said signal thatthe switch cannot be changed while a car is upon the section of track controlled by that signal, except by iirst closing the local circuit by hand at or so as to cut out the point opened by the signal mechanism, and preferably thereafter completing the local circuit by a disengagement of the switch arm or lever preparatory to moving it by band.

In connection with the usual signal it is preferred to employ a separate and especial hand-operated signal to indicate that the cars on the section are being switched, this switching signal being shown as adapted to actuate the circuit-closer to close the local circuit over the point opened by the signal, asjust described.

The switch arm or lever is so connected in the main signal-circuit that should it be unlocked and the switch-rails be moved at all out of the line of the main track, the signal will show danger.

In order to make it the more certain that the engineer shall see that the section is in working order as he enters upon it, and that the rearward approach to his train is properly guarded by the signal, the latter is herein shown as located at a short distance Within the section from its end, so that the train occupied by the engineer which controls the signal of the section upon which he is just entering will operate the said signal just before he passes it.

Figure l is an enlarged plan view of the switch and its operative mechanism and devices to lock it in place, the switch being locked on the main track, the cover or guard for the switch-locking device and its operating electro-magnet and bell being omitted. Fig. 2 is a section ot Fig. 1 on the dotted line a: x, and Fig. 3 is a partial end view of Fig. 1. Fig. 4 is a side view of the signal-post with the main signal at danger,7 and with the switchsignal applied as it will be only when a train on that section of the track is to be switched off on a side track. Fig. 5 is a detail of the signal electro-magnet and its connections for operating the signal to safety.77 Fig. 6 represents a plan view of a section of a railway, supposed to be one mile (more or less) long, with the signal-station at one end and the switch and its operating' mechanism at the other end, the switch being set for the branch track, the signal being omitted to avoid confusion. The switch-lookin g mechanism therein shown is somewhat different from that shown in Fig. 1. Fig. 7 is a side elevation thereof', but showing the signal set for dan ger.7 Fig. S is an enlarged pian of the switch and its operating mechanism of Fig. 6 and devices to lock it in place automatically, the switch being locked on the main track, the cover or protecting-box or guard for the switch-locking device and its electro-magnet being omitted. Fig. 9 is a sectional detail of the said protecting cover or guard. Figs. 10 and 11 are respectively a plan and end view ot' a modified t'orm of parts, whereby the switch arm or lever is unlocked, the local or switch circuit is broken, and the signal is turned to dangerg and Fig. 12 is a detail ot' some of the devices shown in Fig. 1 in a different position.

a and a. represent the rails of a main line ot' track, b b the usual switch-rails, and c the rails ot the side track.

The switch-rails are held in a shoe, d, connected by link e with the cranked or other usual shaftf of the switch, the said shaft having an attached arm or lever, g.

The main signal-circuit is as follows, viz: The rail a (see Fig. 4) is connected by wire 2 with (see Figs. 4 and 5) one electrode of the electro-magnet It ot the signal, the opposite electrode being connected by wire 3 with the rail a'.

One of the switch-rails b is connected by wire 4 (see Fig. 1) with the circuit-closing spring t', having a co-operating contact-point, j, which, in turn, is joined by wire 5 with the track a beyond the switch-rail. The rail a is in circuit with one pole of the batteryA,while the rail t is in circuit with its other pole, and the wire 6, which bridges the switch at 7, connects the said rail t with the switch-rail b, thereby completing the main circuit.

The signal k is located near one end ot1 a section ofthe track in which the switch-stations The local circuit between the signal and switch stations, which controls the automatic switch-locking device, starts from battery B and connects by wire 10 with one electrode of the electro-magnet l, which controls the locking device for the switch, and the opposite electrode ot the said electro-magnet is joined by wire 11 with the metallic stand m, having a contact-point, a, which at suitable times, as hereinafter described, may touch the circuitclosing spring vo, connected by wire 12 with wire 6 and rails at b,and the rail a beyond the switch-rail b at the signal (see Fig. 4) is joined by the wire 2 with wire 13, attached to a circuit-closing spring, p, (herein shown as located between the armature r and magnet h of the signal,) as in Figs. 4 and 5, and the said varmature r, having contact at its inner side with the spring s, isjoined by wire 14 with wire 15, connected with the metallic stand t, provided with the contact-screw u. fire 15 is joined with a metal stand, w, having a contact-point, w, which connects with the circuitclosing spring or transmitting-key y, attached by wire 16 with one electrode of the electro-magnet z, the opposite electrode oi" which is joined by wire 17 with the other pole ot' the battery B.

It is obvious that this local circuit may be completedthrough an independent wire, 18, (shown in dotted lines, Fig. 6,) which will join spring 0 with stand t; but in such modiiication the wire 2 would not be employed to form part of the local circuit for the interlocking switch, and the rail would not be used iu the said local circuit, the said rail being used only as a ground.

The signal lc herein employed operates substantially as described .in my application for Letters Patent of the United States, tiled August 14, 1879, to which reference may be had. In that application it is described that the sig'- nal is electrically held to safety 7 by the operation ot' a closed circuit, and is set to danger77 by the action ot' the train on that. section of the road protected by the signal, the said train through its wheels and axles on the rails short-circuiting the current and demagnetizing the signal electro-magnet.

The switch-stations (one or more) are joined in the same local circuit with the signal.

The switch arm or lever g has at one end ot it a perforated stud, a2, with which engages the perforated end of the hinged switch-holding arm b2 when the switch is in place, as in Figs. 1 and 8, the locking-pin c2 being at that time inserted in the hole in stud a?, so as to keep arm b2 down, in which position the spring d2, the tendency and purpose of which are to lift the arm b2 when the pin c2 is absent, is depressed. This arm b2 is always engaged with and disengaged from the switch arm or lever g by hand, and the arm and spring are mounted upon a suitable plate, a3,'or framework, which also has connected with itthe electro-magnet Z and other parts in electric connection therewith, as shown in Fig. 1, but

IOO

p it will be understood that all the said parts,

with the exception of the switch-holding device b2, spring d2, and arm g, will, in practice,

be covered by a strong box or cage, so as not to be accessible to a person at the switch. This protecting-box is shown at b3 in Fig. 9.

Projecting laterally from the switch arm or lever g is an arm, e2, suitably shaped to be engaged by the switch -locking device f2, which, as herein shown, is a hooked pivoted catch, operated by a lever, g2, having connected with it an armature, h2, which at the proper times, or when the locking device is to be lifted and the switch is Vto be changed, is attracted by the electro-magnet l, made operative from the signal-station. When the armature is attracted the tap i2 sounds the gong and lifts the catch from the notch e3 in the arm e2, leaving the latter free to be drawn laterally out from the box.

The under front face of the catchis beveled, so that the catch, when the armature h2 is unattracted, is free to act by gravity and engage arm e2 and lock the switch-lever g automatically whenever the switch is brought to position, and-it is obvious that the said switcharm will be firmly held locked until released electrically, as will be hereinafter described.

By means of the tap-bell and transmissionkey y at the signal-station and lever b2 at the switch the train-hands may communicate in the usual manner.

In Fig. l the lockingdevice f2 has its axis in bearings of a stand, jz, and the free end of the locking device has a finger, 702, which extends over the lever g2, which carries the armature h2, so that as the said armature is attracted the locking device is lifted from engagement with arm e2.

In Figs. 6, 7, 8, and 9 the armature-lever g2 has the locking device f2 connected with its axis of motion, the two forms being, in operation, equivalents. r

Upon theframe-work a3 is a metal stand, m, provided with a contact-point, n, and connected with wire l1; and when the switchholding lever b2 is fastened, as in Figs. 1 and 8, the said contact-point rests just above, (see Fig. 3,) but so as not to touch, the circuit-closing spring o, connected with wire 12, the said circuit-closing spring being depressed below its normal position by the lever b2, thereby breaking or leaving open at that place, the local circuit. This spring 0, operating with point u, constitutes the secondary circuit-closer to complete the circuit previously connected at the signal-station, as hereinafter described.

The shunting-wire 19 in all the gures extends from wire 12 to a metal stud, Z2, and a metal spring, i, in connection with wire 4 in Fig. 1, .and with wire 5in Figs. 6 and 8, is held by the switch lever or arm g, as in Fig. l, or by its projecting arm` e2, as in Fig. 8, out of contact with the said metal stud; but if the switch arm or lever is at all moved out of true place from any cause, the springt, Fig. 1, permits.` the point or spring j to meet the metal stud l2 andclose the circuit at that point, or,

as in Fig. 8, the springt will itself meet the stud l2, which will shunt the circuit, and thereby demagnetize the signal electro-magnet and set the signal to dangerJ In Fig. 1, m2 is a stop-pin, to limit the out-l In Fig. 6 the switch is unlocked and the switch-rails are set for the side track, the signal is turned to dang-eig7 and the switchingsignal 02, (see Fig. 4,) to'be hereinafter described, is also down. As soon as the switch is closed and in position to be locked by the lever b2 the person at the switch depre'sses, the said lever b2 a few times, using it in the manner of a transmitting-key to break and make the local circuit and sound the bell at the signal to notify the flagman, so that he may remove the especial switching-signal and return to the train 3 or the said lever h2 may be so used as to communicate any other message between the switch and signal. The operator at the signal will use the lever y as his transmitting-key. 1

The arm b2 being locked and the circuit be ing normally held open at u o, the automatic, locking device will en gage and hold the switcharm.

The circuit governingthe switch is closed at the signal by the armature i" of the signal electro-magnet h when the said electro-magnet is excited by a current from the battery A at the opposite end of the section, there being 4no metallic connection across the rails, as by the wheels and axles of the car, or interruption of the circuit from any cause, as by a break in the rails, or wires, or battery, or switch.

When the armature r is attracted by the signal electro-magnet h itis brought into contact with spring p,.thereby closing the local circuit through wires 13, 2, and rail a, also keeping the signal at safety When the` parts are in this position the switch may be operated as follows: Raising the holding-arm b2 closes the local circuit at m a, thereby raising the locking device and allowing the circuitclosing spring z' to throw the lever gout, at the same time breaking themain signal-cir- IOO IIO

cuit at 't' j,and afterward shunting it over when the signal is set to danger before the opening of the switchthat is, when it acts as a block-signal set by a passing train or otherwisethat it affects the locking device to automatically lock the switch.

When it is desired to use the section for switching a train is usually on the section, and the signal consequently at danger When this is the case the local locking-circuit is open at p i and the switch locked, so that raising the arm b2 and closing the points m n does not close said circuit, which must be done before the switch can be moved.

The local circuit is closed to release the locking device by the primary-circuit closer p2, shown in Fig. 4 as pivoted, provided with a metal holding-arm., q2, and a metal counterbalance, r2, the normal condition of the said circuit-closer being as in dotted lines, so as to break the circuit between the contact-points s s2. This primary-circuit closer p2 is turned into the full-line position, Fig. 4, in any proper way, to thereby partially make or connect at that point the local circuit between s s2.

As herein shown, this circuit-closer is arranged to be turned by the weight of the especial switching-flag o2 inserted in the socket q2.'

The local circuit being thus partially completed, the switchman may disengage the holding-arm b2 from the switch arm or lever g, which arm b2, when partially raised? by the spring cl2, but not Jfully removed from stud a2, permits the spring o of the secondary-circuit closer to touch the contact-point n, and thus coin plete the local circuit, when the armature h2 is at once attracted by its electro-magnet l, and the switch-locking device j is raised to release the switch arm or lever g, when it may be turned to do switching. During all this time the signal stands to danger, and it must so stand until the switch is again closed and held in place.

As soon as the switch-arm is automatically locked by the locking device the circuit is again closed through spring t' and its contactpoint, as hereinbefore described, and the electric circuit, no longer 'being shunted, is closed through the electro-magnet of the signal, setting the signal to safety, provided the train has left the said section.

When a train is on the section, or a rail or wire is broken, or a switch open, the armature of the electro-magnet h, being no longer attracted, is thrown away from the said magnet by a spring, s, the end of which bears against Ithe inner face of the armature t, opening the nal, and being without the automatic locking device, the method of demagnetizing the signal-magnet so as to turn the signal to danger by unlocking the switch may be modied, as shown in Figs. 10, 11, wherein the arm g is adapted to be locked by the pin c2, a spring, u2, being employed to move the arm g when unlocked, so as to break the main circuit.

The switch-stand a3 has a connecting-screw, v2, which is insulated by a rubber bush, wz,

' from the stand, and connects with the arm g when locked.

The battery Ais connected with the rails of the main track, as shown in said Fig. 10.

rIhe screw t is connected with the rail a' by a wire, 20, and the spring u2 through wire 21 with the switch-rail b, the rail-circuit and its connections atithe signal-station being as before described, thus making a closed circuit and holding the signal to sat'ety5 but as soon as the pin czis withdrawn the arm g is thrown out of connection bythe spring u2, and the sequently the signal-magnet is thoroughly demagnetized.

Ifdesired, I wish it to be understood that the spring 0 and point u ofthe metal stand m, hereinbefore denominated the secondary-circuit closer, may4 be entirely dispensed with, the wire'11 in such event beingunited with wire 12, as indicated by the heavy single dotted line 22 at the right of stand m, Fig. 1. In such plan the switch-lookin g device would be electrically disengaged from the switch arm or lever as soon 4as the primary-circuit closer p2 was operated.

It will be noticed in this moditication so long as the switch -arrn is engaged by, the switch-holder, and the electric apparatus in order, and no train upon the section of track, that the signal for that section of track will always stand to safety, and at the same time the switch-locking device will, by means of its controlling-armature and electro-magnet, be held disengaged from the switch-arm, for the train being absent from the section permits the electro-magnet l to be excited by the closed circuit at, the signal electro-magnet; but as soon as a train arrives upon the seetion the electric current, bein g sh unted through the wheels and axles, demagnetizes the signal electro-magnet and permits the switch-locking device to automatically fall, lock, and hold the switch-arm in position so long as the train is upon the section, unless the steps hereinbefore described for switching have been taken.

I wish it to be understood that the signal electro magnet, when demagnetized by the shunting of the circuit by the presence of the IOO IIO

train on the track, will positively insure the locking ot' the 'automatic switch-locking device.

In this specification I have in Figs. 6 and 8V shown and described how a circuit-closer on the main line may be operated to close the main-line circuit, the device or arm e2. which actuates the said circuit-closer, being attached to the switch arm or lever; but I expressly ferred to as already filed, and it will therefore be understood that the shatt carrying the signal will be operated mechanically at proper times to change the position ot' the signal, and that the si gnalv electro-magnet Y will at the proper time operate an armature-lever, which will release a detent, all substantially as described in the said application.

I have described the interlocking' switch as used in connection with a block-signal operated by a closed rail-circuit; but it is obvious that it may be used with any block-signal, either operated 'mechanically or electrically, it being only necessary to have a circuit-closer in the circuit which actuates the locking device controlled by the said signal, itself under control of the passing trains, so that the circuit is in condition to lock the switch while the signal indicates danger,77 and to retain it unlocked while the signal indicates safety.77

It is obvious, also, that an independent signal in the circuit controlled by the circuitcloser 'i may be used to be set by the opening otl the switch; but such signal should be placed between the block-signall and the switch, and its operation would be entirely independentot the locking device.

I am aware that a switch-locking device controlled by an electro-magnet has been used to retain the switch-arm locked until after the signal for open switch has been set, such a device being merely a check upon the proper action of the switch-signal, and performing no importan tfunction while the parts are in proper working order.

The essential feature of my invention is that the switch cannot be accidentally or maliciously changed after a train has passed the last block-signal before arriving at the switch, as might be done in other systems of signaling, and the locking may be used independently of any visual signal, as it is evident that the signal-magnet merely acts as a relay in closing the secondary or locking circuit.

When used in connection with the closed rail-circuit, as herein shown, the electro-magnet Z might be placed in what has been herein called the primary circuit, in which case it and the locking device would be operated directly by the train. In such an arrangement an independent circuit controlled by hand from a point not-in reach of the man at the switch would be necessary for unlocking the switch.

I am aware that a secondary signal has been used located a short distance within a section and dependent on a primary signal for its movement; .but I am not aware of an v signal yapparatus arranged, as herein described, so

that the main signal turns to danger just as the engineer is passing it.

I claiml. In an electric railway-signal apparatus, a switch and switch-locking device, to automatically engage and lock the switch-rails or their moving mechanism when the switch is closed, and an armature and electro-magnet to operate the locking device, and a circuit therefor under control ot' a passing train, substantially as described.

2. In an electric railway-signal apparatus, a block-signal to be operated by a passing train, and a circuit-closer operated by said signal to control an electric circuit, and a switch-operating arm or lever, a switch-locking device, and an armature and electro-mag- 4netto operate it, the said electro-magnet being connected in the circuit controlled by the block-signal, substantially as described, whereby the switch-locking device is caused to automatically lock the switch arm or lever so long as the signal indicates danger, as while a train is on the said section of track in which the said switch is located, substantially as set forth.

3. In an electric railway-signal apparatus, a switch-operating arm or lever, a guarded switch-locking device, and an armature and electro-magnet to operate it, the said armature and magnet being connected in circuit, substantially as described, combined with' a circuit-closer to partially complete the circuit in which the switch-locking` device is located, a secondary-circuit closer, and a switch-holder, whereby,when the switch-holderis disengaged from the switch arm or lever, the secondarycircuit closer is made to complete the said circuit and operate the armature of the switch- IOO IIC

IIS

locking device and disengage it from the switch arm or lever, to permit the switch to be moved or changed when the train is upon that section of track, substantially as dcscribed.

4. The combination, with the switch arm or lever, its automatic locking device, and an armature and electro-magnet to operate said locking device, ot' a circuit-closer in the circuit of said electro-magnet, and a hand-operated switching-signal to control said circuit-closer, substantially as and for the purpose set forth.

5, In an electric railway-signal apparatus, a switch-arm and locking device therefor, combined with a block-signal mechanism electrically connected with the said locking device and controlled by the train, whereby the train is enabled to control the signal, causing the latter to lock the switch, substantially as described.

6. In an electric railway-signal apparatus, a switch-arm, a switclrholdcr, and an automatic switch-lockingv device, and an arlnature and electro-magnet to disengage the switchlocking device at the proper time, the said electro-magnet being located in an electric circuit provided with a circuit-closer operated 1c by the switch-holder, and another circuitcloser operated by hand at a distance from the switch, substantially as described.

7. In an electric railway-signal apparatus, a switch-arm, a switch-holder, switch-locking device, and electromagnet and armature to at vthe proper time disengage it from the switch-arm, combined with a signal controlled by the train on the section, with which signal the said parts are in electric circuit, substanzo tially as described.

8. In an electric railway-signal apparatus, a signal electro-magnet normally in closed circuit when the train is absent from the section of track and switch-arm fastened, combined 2 5 with a second el cetro-magnet to disen gage the "that section of track, combined with an electrdmagnet to release and permit the switch- 3 5 `looking device to engage and hold the switch locked while the train is on that section of tra'ck or the electrical apparatus is out of order.

10. In an electric railway-signal apparatus,

a circuit-closer in a local circuit controlling a switch, as described, provided with a socket to receive a visual switching-signal to'operate the said circuitcloser, substantially as described. l

1l. The switch-arm, combined with a circuitcloser in circuit with the signal electromagnet, and a shunt-circuit, arranged as described, whereby, when the switch-arm is in position to close the switch on the main track, the circuit with the signal electro-magnet is closed, but the moment it is released to move the rails the said circuit is iirst broken and then shunted, substantially as described.

l2. The switch-arm, combined with a circuit-closing spring to move it when unlocked, the said spring at that time breaking the circuit on the signal electro-magnet, substantially as described.

13. In a railwaysignal apparatus, a switch and switch-lookin g device and a visual signal operated by an electric circuit having a circuit-closer operated by the movement of the switch mechanism, and a secondary circuit which controls the switch-locking device and has a circuit-closer operated by the signal, when arranged, substantially as described, to cause the secondary circuit to be operated by the signal after the switch mechanism has moved from a 'position t0 be controlled by the locking device, substantially as described.

ln testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

oscAn eAssETT.

Witnesses:

G. W. GREGORY, A. J. DUNN. 

